Saadiyat Island, Natural island within Emirate of Abu Dhabi, United Arab Emirates.

Saadiyat Island is a natural island 500 metres off the coast of Abu Dhabi, enlarged with reclaimed sand in a mangrove zone and covering about 26 km². It is linked to the city by the 1.4 km Sheikh Khalifa Bridge, a ten-lane crossing opened in 2009. Its western end holds the 2.43 km² Cultural District, with the Louvre Abu Dhabi's white lattice dome among its museums.

Saadiyat is a natural sand island in the mangrove zone, enlarged by reclamation to expand Abu Dhabi's building and beach land. The Tourism Development & Investment Company developed it under a master plan by EDAW, continued by AECOM, with Al Jaber building villas and HILALCO the roads and infrastructure. The Sheikh Khalifa Bridge, 1.4 km long, has linked it to Abu Dhabi and Yas Island since 2009.

The Arabic name jazīrat as-saʿdiyyāt means "Island of Happiness". Manarat Al Saadiyat hosts the annual Abu Dhabi Art fair and a permanent Saadiyat Experience exhibition on the island's development plans. The Abrahamic Family House, opened on 16 February 2023, groups a church, a mosque and a synagogue with shared conference rooms.

Taxis and public buses connect the island to Abu Dhabi, with travel taking around 20 to 30 minutes from the city center. Well-defined pathways link the main areas, and parking is available for those exploring by car or on foot.

The island is a natural sand core in a mangrove zone, enlarged and reinforced with additional landfill rather than built entirely from scratch like Dubai's Palm Islands. Its 1.4-kilometre Sheikh Khalifa Bridge, opened in 2009, links it to Abu Dhabi and Yas Island.